地质科技情报2017，Vol.36Issue(3)：122-129,8.DOI:10.19509/j.cnki.dzkq.2017.0316
重庆黔江地区下寒武统牛蹄塘组页岩气成藏条件
Shale Gas Accumulation Conditions of the Niutitang Formation of Lower Cambrian in Qianjiang Area, Chongqing
摘要
Abstract
The Lower Cambrian Niutitang Formation is an important strata to be expected to achieve shale gas exploration breakthrough after the Lower Silurian Longmaxi Formation is discovered in Qianjiang,Chongqing,but its exploration direction is still not clear.By drilling core and outcrop observations,combined with microsections,SEM,all mineral and clay mineral X-ray,organic geochemical parameters,as well as numbers of experimental test methods,we have analyzed shale gas accumulation conditions systematically of this Lower Cambrian Niutitang Formation in Qianjiang,Chongqing.We focused on sedimentary environment,organic rich shale distribution and buried depth,organic geochemical index,reservoir,preservation conditions and characteristics of gas.The research shows that the Niutitang Formation was in shallow-deep water shelf transitional sedimentary environment,and its organic rich shale is distributed in the lower part of the strata with the thickness ranging from 40 to 80 m.The organic rich shale has great geological conditions for the development of shale gas reservoirs,with high TOC ranging from 2.0％ to 6.0％,and Ro being over mature stage.Its organic matter is dominated by type I,with great hydrocarbon generation and the hydrocarbon generating strength can reach in 5 × 108 and 20 × 108 m3/km2.It also has high brittle minerals,and the clay minerals are almost illite and illite/smectite.The shale reservoir space types are varied,with low porosity and ultra-low permeability characteristics.Comprehensive analysis of the evaluation indexes reveals that these areas,including the west of Qianjiang-Zhuoshui-Youyang,the east of Pengshui,the south of Yushan-Qiangjiang and the north of H ongdu-Youyang,have great shale gas accumulation conditions.These areas could be the favorable areas for shale gas of the Lower Cambrian Niutitang Formation in Qianjiang,Chongqing.关键词
重庆黔江/牛蹄塘组/页岩气/成藏条件/有利区带Key words
Qiangjiang, Chongqing/Niutitang Formation/shale gas/accumulation condition/favorable area分类
天文与地球科学引用本文复制引用
赵瞻,余谦,周小琳,刘伟,何江林,谢渊..重庆黔江地区下寒武统牛蹄塘组页岩气成藏条件[J].地质科技情报,2017,36(3):122-129,8.基金项目
中国地质调查局项目“四川盆地下古生界海相页岩气基础地质调查”(121201010000150004) （121201010000150004）
